Diamondbacks Designate Miguel Castro For Assignment, Cristian Mena to IL

The D-backs part ways with one of their relievers, and place one of their prospects on the injured list.

Jul 22, 2024; Kansas City, Missouri, USA; Arizona Diamondbacks relief pitcher Miguel Castro (50) pitches during the fourth inning against the Kansas City Royals at Kauffman Stadium. Mandatory Credit: Jay Biggerstaff-USA TODAY Sports / Jay Biggerstaff-USA TODAY Sports

According to the team, the Arizona Diamondbacks are designating right-handed reliever Miguel Castro for assignment. The DFA comes as a corresponding move, freeing a roster space for newly-acquired reliever Dylan Floro.

Castro rode a tumultuous career with the D-backs. Arizona had signed the hard-throwing righty to a deal ahead of the 2023 season, complete with a vesting option for 2024.

Castro began the 2023 season to great success. Through June 2nd, he posted a brilliant 2.13 ERA and was pitching extremely well in a high-leverage role, including part-time closing duties.

A disastrous blown save against the Atlanta Braves in his next outing was the beginning of Castro's decline. He finished the 2023 season with a 4.31 ERA, identically matched with a 4.31 FIP. His strikeouts were down, and his home runs spiked.

Part of his overall drop in numbers might have come as a result of extreme use, as the reliever pitched 64 2/3 regular season innings in 2023, before pitching another eight in the postseason.

In 2024, Castro only appeared in eight games to begin the season, pitching to a 5.19 ERA over 8 2/3 innings. He was then placed on the 15-day IL on April 23rd, dealing with right shoulder inflammation.

He wouldn't make his next appearance until July 13th. He made three appearances, allowing eight hits, two walks and two home runs, leading to four earned runs over five innings. He only threw 13 2/3 innings for Arizona this season.

His sinker, which profiled as a high-powered pitch, complete with both velocity and movement, had dropped significantly in velocity. Although averaging 96.8 MPH on the pitch in 2023, Monday night's appearance saw the sinker top out at 93.8 MPH.

With Dylan Floro already in Phoenix and able to join the club right away, Castro will be the odd man out, and will, in all likelihood, end his tenure with the D-backs' organization.

Cristian Mena Placed on 7-day IL

In addition to Castro's DFA, the D-backs will make a roster move in their minor league system.

Right-handed starting pitcher Cristian Mena, who made his MLB debut in early July, was placed on the 7-day injured list by the Triple-A Reno Aces. Baseball America lists him as Arizona's No.12 prospect.

D-backs Farm Director Shaun Larkin confirmed to Sports Illustrated it was a forearm strain, and the righty won't throw for eight weeks, likely ending his season.

Mena, 21, started one game for the D-backs, going just three-plus innings against the Los Angeles Dodgers. He allowed three walks, four hits and two home runs on 70 pitches, and was charged with four earned runs.

Since coming over from the Chicago White Sox in a deal for outfielder Dominic Fletcher, Mena has had a mixed bag season in the minors. He began the year strong, but his ERA spiked, currently sitting at 4.61, albeit in the very hitter-friendly Pacific Coast League.

His last outing saw him go six strong innings, allowing just one unearned run on four hits whole striking out six, but it appears unlikely he'll have the chance to continue an upward trend in 2024.